Schlumberger

Data Analysis

To better interpret, model, and monitor production data, rely on our real-time online data analysis tools including pressure transient analysis (PTA), production evaluation (RTA), and traditional reservoir/production simulations. 

Production Evaluation Workflow (Rate Transient Analysis, RTA)

The production evaluation known also as the rate transient analysis (RTA) workflow enabled in the Advanta system utilizes this type of low-frequency production data. The key parameter from production evaluation interpretation is the well drainage area; however, additional reservoir and well parameters, including permeability, skin, fracture half-length, and fracture conductivity can also be interpreted.

Production History

Production history is converted into a constant rate solution, utilizing material balance time. While material balance time represents the exact superposition time for boundary-dominated flow, it also represents an acceptable approximation for other flow regimes, such as linear and radial flow (Anderson, 2003). The flow regimes exhibit certain slopes on these plots that facilitate identification and parameter interpretation (Zhou, 2009).

Specialized Petroleum Engineering Plots

  • Rate normalized index (RNI) plot-also referred to as log-log or normalized pressure integral (NPI) plot (Blasingame, 1989)
  • Blasingame plot (Blasingame, 1991)
  • Agarwal-Gardner plot (Agarwal, 1999).

The software also implements Poe's analysis of production data from fractured wells, converting production data into a constant pressure solution using superposition time for fracture flow regimes from which fracture properties can be inferred (Poe, 1995). Poe's technique and the analysis of other plots serve to calibrate each other.

Traditional Reservoir Simulation Workflow

The traditional reservoir simulation workflow uses production rates (daily or sporadic) as input to match flowing and average reservoir pressures in a multiple-well environment. The flowing pressure data may be sporadic or may only contain a few points because the workflow does not require demarcation of pressure transients. The history-matched reservoir model enhances prediction of behavior performance of the reservoir/well system.